 Dwi'n du'r rhaid o'r hollien i ddod Ieithio ddod o geoarchialoedd Dwi'n ddod o'r hollien i ddod Ieithio dyna ar y cyfnod a ddod y gallwn ei bwysig Ac mae'r hollien i ddod o cael ei ddod A ddod o'r hollien i ddod Yna ddod i ddod i ddod Mae'r hollien i ddod Mae'r hollien i ddod when I presented all the data from the two sites in Ahus, and he asked, can you identify if there is geoarchaeological signature that sort of defines what is urbanism. So I thought I would use this to sort of theme the data from the two sites. Rwy'n cyfnodd yma, rwy'n cyfnodd, ym Riga, yma'r capital modern y Llatwy, ac yn ym Mhysgol Unesgo, ym Rhysgol, a'r Rhysgol Rhysgol yn y UK. Rwy'n cyfnodd yma, mae'r cyfnodd yn y fronteas, sy'n cyfnodd yma, sy'n cyfnodd yn y cyfnodd, ..a dynamic zones of mobility and acculturation. They allow us to examine the catalyst for urban development. The geoarchaeology in particular helps us to understand how the cities develop in frontier zones. To what extent the structuring and the range of activities that take place in towns are an expression of a controlled process of urbanisation. What do these two sites have in common? We have one site that's a really bustling modern city, a UNESCO World Heritage Site. And then we have another that is just sort of doesn't exist anymore and is in a field in Berkshire. Well, both have Iron Age origins. They both have an Iron Age settlement below. Silchester was on the frontier of the Roman Empire in the southeast corner of Britain. The establishment of Riga is synonymous with the Livonian Crusades in the Baltic. There are some differences. Silchester was abandoned and is now a sort of what we call a greenfield site. Riga is a major urban centre. The way the data has been acquired is also quite different. Silchester was a research excavation run by the University of Reading and also a field school. Whereas the excavations in Riga were carried out by a commercial company ahead of development. So, just to show where Silchester is. The excavations at Silchester have allowed the town to be studied from beginning to end, providing a snapshot. Of town life from the late Iron Age period all the way through to the early medieval period. At the Iron Age town was the political territory of the Atribatis tribe. In about AD 44, we have the conquest of Britain in AD 43, but from about AD 44 onwards. You see signs of a military presence, but there's no military buildings, just artefacts. We then see a sort of programme of road building. So, we have roads built across Iron Age buildings and then there is a sort of first major phase of buildings from the Roman period. However, these buildings, they don't conform to the Roman street grid. So, it's a bit sort of anarchic. They sort of keep the Iron Age orientation. And then, it's not until the third century AD where you have a second major phase of buildings that the buildings are then aligned to the Roman street grid. Fifth century, the formal administration of Rome ceases. And this sort of town sort of falls into decline. We have dark earth deposits forming and buildings sort of robbed away, this sort of thing. And at that point, the town sort of falls on another frontier. So, it's a frontier town. It's beginning and it's end. So, it falls on the early medieval Wandsdike frontier. So, you have Wessex at the south and Mercia to the north. This just shows where the excavations took place. So, there have been excavations in Insela 9 at the top. These went on for several years between 1997 and 2014. And then there have been more recent excavations in Insela 3. So, the excavations in Insela 9, they started in 1997, I suppose, when geoarchaeology wasn't really routinely applied. I did my PhD research and it sort of wasn't really until then that we started doing techniques such as micromorphology, for example, and geochemical analysis. On sediments. So, this one meant that we sort of missed the later phase of the town in terms of the sampling. However, we've managed to sort of get it in Insela 3, which is not very far away. So, this has allowed us to look at the dark earth deposits and the later occupation. So, the other site that I'm going to talk about is here. And this fits within the framework of the Livonian Crusade. So, between 1198 and 1290, Enriga itself is founded in 1201. So, if I go back and start with Silchester, sorry about all the text, the geoarchaeological data from sort of internal spaces at both sites has allowed the spatial organisation of activities to be studied, both spatially and chronologically, at high resolution to sort of look how the inhabitants' lives changed as a result of political change. And the geoarchaeology has been instrumental in both sites in looking at resistance to change and the retention of traditions harking back to the Iron Age, for example. So, at Silchester, we were able to look at urban life from the opidum through to the abandonment. And the geoarchaeology from the Iron Age period is actually really boring. I've looked at the geoarchaeology from the pits and there's just nothing in them, just like gravel. There's no bone, there's no ash, there's no bits of pottery, there's larger sort of fragments of pottery, so where something's been smashed and thrown in. But in terms of the micro refuse, there's just nothing there, probably because there's not really any people there. So, it's quite quiet at this point. This sort of gradually changes through time, so I've just finished some work on what we call period one, which is just around the conquest time, just before conquest. And you still have these sort of buildings with central halls, like you have in the Iron Age. It's very sort of domestic in their use, very multifunctional spaces, so everything going on in that building around the hall. And we have the use of mats as well, which is nice, because it's not something you see in the later phases. So after conquest, this sort of tradition persists with these activities around the central hall. And then there's a gradual move away from this Iron Age tradition, with separate rooms added, and the separation of space, so different buildings used for different activities. So these are some of the buildings from what we call period two, period three. So around 70 to 150 AD. And the ones that I've circled are the most interesting buildings. The red dots within them are the hearts. So you can see the one at the top, which is called ERTV one. That started off as a single room structure. With all the sort of activities taking place. The grand patch of room two, that is lots of trampled material. So that's where the doorway was, which wasn't visible from the superstructure. Even though you can sort of see it's cut, that was actually Victorian trench, where the Victorian excavators had just truncated it. That wasn't actually the doorway. The doorway was identified using micro stratigraphy. So we have this sort of single room structure. The activities taking place around the half. And then a new sort of room one is added at a later date. ERTV eight you can see here. Again that's quite a dynamic structure that also started off as a single room. And it has a post hole structure and earlier iron age structure below it. And all these buildings start in a similar way. You can see here we have a round house. Still into the Roman period. So this is the annex here. And this is the section through the profile of the annex. And here you can see this is an opus signina floor. Opus signina in the rest of the empire is just like a sort of bog standard mortar. It's nothing particularly special. It's used in walls. It's just a functional material. But here it's used in this sort of building on the fringes of the empire. It's seen as quite special and it's used as the floor. And it's kept very clean during its use. So there's no buildup of refuse between this deposit here and this earthen floor that's used as a replastering afterwards. This then sort of falls out of use. So starting off having this nice sort of opus signina floor then going to have this earthen floor. It then has this big dump of recycled floor, latrine waste, bits of tile. Just used as a levelling deposit and this covers the sort of beam slot here. So very much a complete change in use for this building. It has bits of phosphatised bone, all sorts of stuff in it. So it's no longer the nice clean annex that it once was. You can see the outline. This is the outline of ERTB1 here. The main focus of the habitation has now shifted here. These are the floors of the new building. Overlying what was once ERTB1 is just loads of trampled done. So it's now used as an area where animals are kept. It has all these laminated clay coatings which being able to look at these on an open area excavation has been quite handy because they can be quite hard to understand their origin and difficult to interpret. But being able to look at them spatially, I've sort of tentatively been able to look at open spaces or semi open spaces that might exist. So where you have sort of clear floors, internal spaces, you don't tend to get where you don't get these sort of micro laminated clay coatings. However, in this space here, with all this latrine waste and trampled material, where it's a bit more sort of open, I've started to get these micro laminated clay coatings which led me to the interpretation that this is not a roof space or a semi open space for example. So we've also looked at the XRF geochemical data. This has been plotted spatially. So you see the alignment of the buildings here. This is the grid site. So this building is ERTV1 at the top. This one here is ERTV8 at the bottom right. This is copper to zinc, lead, strontium, phosphate and calcium. So you can see there's quite a lot of variation between the buildings and this is after the conquest period. This is where you start to see the separation in the use of space. So yellow is low and then the sort of darker black colours are high. So this one here, for example, this is over 1000 ppm of copper in that building. So this is sort of what we would say is half the red dots are half. So we have some sort of metal working taking place, copper alloy metal working taking place on that part. We've also got high zinc. And this building, you can see the phosphates. This is a really quite a dirty unclean building particularly compared to some of the other buildings and you can see it here and all the sort of geochemical signatures. You've got the phosphates appearing in that building there which are probably leached through the profile because you have the later stabling deposits directly over it and I think they've washed through the profile. But these sort of differences in the buildings are also visible in the micromorphology. So the micromorphology from ELTB8 is just packed full of dump deposits. There's just dumps on top of each other, rake-out material from the haws left around them. So it wasn't a clean building unlike some of the others, particularly ELTB1. So moving across Europe to the excavations of Riga, these were carried out by a commercial company. The people who took the samples have never taken any environmental samples before. However, they did a very good job and they sampled absolutely everything. So we arrived to work one day and opened the office door and there was a mound of wall of soil waiting for us that had just been piled in its bags in the office. So, and they also collected micromorphology samples, which I still have to look at. However, we have processed the geochemical data and there's been lots of archaeological data collected as well from the site and Zuwark data as well. So this is the plan of the Mogmatel and the yellow circle. It represents where the former liver village was. This is the Iron Age settlement. And this is incorporated into the modern town and that's where the excavations took place. And the excavations took place between 2011 and 2012. And the archaeology was absolutely fantastic. There are loads of superimposed buildings on top of each other, timber-framed, we had latrines, really fantastic preservation of the stratigraphy. The building techniques were also indicative of indigenous techniques from the live village and there was a virtual absence of imported material culture which sort of strongly suggests that this was the area of the live village. So these buildings here, these are, Building 17 is the earliest building that we have dated in Riga. So this is dated to 1209 and Riga was founded in 1201. And what these results show are a very sort of separate use of space between buildings. So Building 15, these are the geochemical results. You can see we've got very high concentrations of lead, copper, so PB is the lead and that's sort of over 3,000 times the background geology so around the site, which is pretty high. It's also 120 times the average for the site. So I took an average across the site as well just because I wanted to see what it was like anyway. It's across the site and I also looked in relation to the background. Copper was also enriched but not as much as lead. So I also, once I got the XRF results, I wanted to put them through the ICP to look for things like tin, silver and gold. I found silver in this building. This is around 47 times the background. So these are deposits around hearts which again shows some sort of lead alloy working. Just outside of this area here, we had a big dump of burnt bone but burnt bone and it's calcine bone but of strange parts of the animals. So like their horns and hoofs and from arthritic animals as well. So the parts that you don't really want. So the old animals and arthritic animals use this fuel. So probably to get the high temperatures required for metalworking. So we have the high levels in the building and then the sort of dump of fuel outside. And there's also a comparison of this from around the Novgorod area as well. In comparison, the other buildings are pretty sterile in terms of their geochemical enrichment. There's not much going on in those at all. No significant geochemical enrichments. These two buildings overlie the ones that I've just shown. This theme of clean buildings and sort of dirty spaces sort of persists through time. It's just a position of the two buildings next to each other. So we have lead also very high. 1,000 times the background around that half. The half is in the middle here. And I then looked in the ICP at the ICP results and we had tin that was over 2,000 times the background. So some sort of pewter working taking place on this half. And I've done some experimental work looking at the geochemistry signatures in sort of experimental buildings in the UK. And what you find is in the primary place of metalworking the soil residues of the elements are very high but this signature drops off very quickly. So even within a couple of metres away from that initial point of metalworking you no longer get these significant enrichments. They're a bit rich, perhaps 10, 20 times the background but nothing like the primary place. And also this was a very dynamic space, a dirty space as well. We have loads of fish bones, fish processing waste and huge dumps of animal bone outside the building which suggests that there was sort of butchery going on. Live animals were slaughtered. And we also have the handling of raw fish within this building as well, this tapeworm evidence. So back to the initial question to sort of sum up is an urban geoarcheological signature. Well, I think there are various factors to consider with this. I think it depends if it's a Roman or medieval town. The Roman geochemical data, the enrichments from Silchester they're nothing compared to what we're getting from Riga sort of throughout both from the sort of early period and the later period. Even when we're getting metal working around hards the enrichments are nothing like this and the general sort of enrichments across the site are nothing like what we find at Riga. So there's probably a difference between whether it's a founded Roman town or a medieval town in terms of the activities that are taking place. It probably depends on the status of the settlement and the range of activities that take place. The size of the settlement and the concentration of the population within it as well. So how packed in everyone is living where the refuse is thrown for example. So I think that's all I have to say. Thank you.